Piezo-electric crystal oscillator system



Juin viii i au: in o L g I I 7 1 l1 ,June 7, 1932. f, Y ,A HUND 1,861,862 n MEANS F02. UTILI lNCr MuLTlPucnTY OScILLArloNS w14 :cH AE PQoauceo F/ menue' L Ane P y PIEZO ELECTRIC CRYSTAL OSCILLATOR SYSTEM 'Filed June 7, 1929 s sheets-sheet 1 W W V y June 7, 1932. A HUND kPIEZO ELECTRIC CRYSTAL OSCILLATOR SYSTEM n .w U

5 Sheets-Sheet 2 Filed June 7, 1929 LIL@ Patented June 7, 1932 UNITED STATES kava-Li una t-uuiai PATENT kOFFICE Auetrsi` HUND, or BETHESDA, MARYLAND PIEZO-ELECTRIC CRYSTAL OSCILLATOR SYSTEM Application led J'une 7, 1929. Serial No. 369,237.

My invention relatesbroadly to piezo-electric crystal oscillator systems and more particularly to a system for utilizvingaymultiplicitloioscillpations existent in a piezo-electric crystal element.

One of the objects of my invention is to provide a piezo-electric crystal oscillator system wherein a multiplicity of oscillations are produced along axes substantially parallel` with the optical axis of the crystal and eiiectively utilized.

ing the mounting of a piezo-electric crystal element for utilizing oscillations along a multiplicity of axes according to my invention; Fig. 7 illustrates one method of establishing connection with the piezo-electric crystal element for utilizing the vibrations described more particularly in the specification hereinafter following; Fig. 8 illustrates a modied arrangement of electrodes with respect to the piezo-electric crystal element; and Fig. 9 shows a further modified arrangement of Another object of my invention is to pro- \electrodes for the piezo-electric crystal ele vide a system for mounting a piezo-electric crystal element for the production of a multiplicity of oscillations along the optical axis thereof for obtaining oscillations of constant frequency in an oscillatory circuit connected i l with the piezo-electric crystal element.-

A further object of my invention isto provide a piezo-electric crystal system in which oscillations are developed along a plurality of axes disposed around the optical axis of a piezo-electric crystal element.

Other and further objects of my invention l reside in the construction of mounting for a piezo-electric crystal element for the production of oscillations along a plurality of axes which extend parallel to the optical axis of v the piezo-electric crystal element, as will be more fully set forth in the specification here! inafter following by reference to the accom; panying drawings, in which:

Figure 1 diagrammatically illustrates a `circuit arrangement embodying the piezoelectric crystal oscillator system of my invention; Fig. 2 illustrates a modified circuit arrangement embodying the principles of my invention; Fig. 3 shows a further modified circuit arrangement embodying the principles of my invention; Fig. 4 illustrates a multistage oscillator system controlled by a piezoelectric crystal oscillator according to the principles of my invention; Fig. 5 illustrates diagrammatically a mounting for a piezoelectric crystal and shows the electrical connection through the several electrodes adj alcent the multiple axes in the piezo-electric Vcrystal system, the oscillations from which are effectively utilized according to my invention; Fig. 6 is a perspective view illustratment of my invention.

Referring to the drawings in detail, refer-y ence character 1 in Fig. 1 represents a cy-K nected with the electrodes of the piezo-electric crystal element, the circuit including electron tube 6 having the input and output circuits thereof coupled for sustaining oscillations generated by the piezo-electric crystal element. A grid electrode 6a has a selected potential applied thereto from battery 7 through resistance 8. The input circuit includes inductancek9. The output circuit includes tuned circuit 10, high potential source 11 shunted by by-pass condenser 11a, and tuned inductance 12. As shown in the modiication in Fig. 3, a capacity feedback path is established through condenser 14 which interconnects the input and output circuits of the tube system. The oscillations through piezo-electric crystal element 1 takes place along components ofthe optical axis, the components extending'parallel to the optical axisf tric crystal element 1 mounted upon an elec-' trode 17 which electrode is connected through conductor 18 with the upper electrode 3. The oscillations through the piezo-electric crystal element occur according to dotted lines 15, 16 and 19 and 20. Tuning of the circuit is accomplished as described in connection with Fig. 1 and feedback is controlled by means of the capacitative coupling 14.

' In Fig. 4 I have shown an oscillator system comprising a multiplicity of tubes 43, 44 and 45 having input and output circuits coupled through resistance elements at 46 and 47 with the output circuit 48, and with the input circuit 49 through the piezo-electric crystal 1. The regenerative action of the circuits is controlled by condenser 50. This arrangement produces constant frequency oscillations which may be utilizedin any desired manner.

In Fig. 6 I have shown diagrannnatically one method by which the several oscillations through the piezo-electric crystal element 1 may be utilized. I arrange the piezo-electric crystal element 1 within a tubular member 13 on which I provide a multiplicity of longitudinally extending contact strips 21, 22,

' 23, 24, 25 and 26 which extend the full length of the tubular member 13 and provide contacting electrodes with the sides of the piezoelectric crystal element 1. The alternate contact strips are connected together as shown in Fig. 8 and provide terminals to the oscil- V- v lator system including electron tube 6. The

circuit including electron tube 6 is placed in a condition of regeneration and then by placing the piezo-electric crystal 1 in a chamber which has been evacuated and helium or other gas introduced therein through a pipe line, the oscillations along the several axes may be observed by virtue of a luminous discharge, the paths of which I have indicated by the arrows 28, 29, 30, 31, 32 and 33. It will be observed that the luminous discharge which takes place along the several axes is remote from the optical axis and defines the paths of the several oscillations which occur through the piezo-electric crystal. I have endeavored to illustrate the several paths clearly in the perspective view in Fig. 6.

In Fig. 7 I have illustrated a system for establishing connection with the piezo-electric crystal element wherein the electrodes 3, 4 and 17 indicated in Fig. 3 actually sur- "des round the piezo-electric crystal element in the form of bands embracing the cylindrical body of the piezo-electric crystal element and providing paths for the oscillations through the piezo-electric crystal element along the several axes thereof. Electrodes 3 and 17 provide one pole for the crystal element and electrode 4 provides the other pole of the crystal element.

In Fig. 9 I have shown a modiiied method for establishing opposite poles for a piezoelectric crystal element. I provide contact strips illustrated at adjacent ends -of the piezo-electric crystal element Where the contact strips are properly poled or connected by jumpers extending between the contact strips. That is, strip 51 at positive potential is electrically connected with strip 52 at positive potential. Strip 53 at negative p0- tential is connected to strip 54 at negative potential. Strip 55 at positive potential connects to strip 56 at positive potential. The other sets of strips are similarly connected. That is, contacts 57 and 58 both at negative potential are connected in series. Contacts 59 and 60 both at posit-ive potential are connected in series; and contacts 61 and 62 both at negative potential are connected in series. All of the contacts at positive potential are bonded through bus connection 63 for connection to the oscillator system, and all contacts at negative potential are bonded through bus 64 and connected to the negative side of the oscillator system. 'Ihev interconnecting members between the contacts are maintained out of contact with the center portions of the piezo-electric crystal.

The several forms of my invention have been found to provide suiiicient means for controlling oscillations at constant frequency. I have found that the oscillations developed along the optical axis of the crystal persist at constant frequency, thus roviding a highly eicient form of constant requency control system.

It will beapparent to those skilled in the art that modifications of the arrangement of piezo-electric crystal and circuit system associated therewith may be made, and while I have described preferred embodiments of my invention, I desire that it be understood that modifications may be made and that no limitations upon my invention are intended other than those imposed by the scope of the 2. In a frequency control system, a sub-V stantially cylindrical piezo-electric crystal j 65, end of said piezo-electric crystal element, and

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. said sleeve and establishing connection with said piezo-electric crystal element.

4:. In a piezo-electric crystal apparatus, a

, piezo-electric crystal element, al tubular member enclosing said piezo-electric crystal element, and a multiplicity ofwelectrodescarried i by said tubula'i'ib`er`f6r establishing connection with said piezolelectric crystal element in a plurality of diiferent positions.

5. In a piezo-electric crystal apparatus, a piezo-electric crystal element, a cylindrical member enclosing said piezo-electric crystal element, said cylindrical member carrying a plurality of longitudinally extending conductive strips, said strips providingr electrical connections with different portions of said piezo-electric crystal element.

6. In a piezo-electric crystal apparatus, a piezo-electric crystal element, a member surrounding and enclosing said element, a plurality of independent conductive strip members extending longitudinally of said member substantially parallel to the optical axis thereof, connections between alternate conductive stripsaround said member and terminals extendmg from said connections.

7. In a piezo-electric crystal element a multiplicity of contact members connecting 40 with the sides of said piezo-electric crystal separate terminals individual to the connections of opposite polarities.`

9. In a piezo-electric crystal system, a piezo-electric crystal element having a substantially cylindrical shape, contact members in the form of strips extending longitudinally along a portion of the cylindrical sides of said piezo-electric cr stal element adjacent opposite ends thereo the Contact strips of negative polarity being alternately positioned between contact strips of positive polarity adjacent each end of said piezoelectric crystal element, connections between contact strips of like polarity at each end of said piezo-electric element, and terminals individual to the connections of each polarity of the charges generated by said crystal system. p

In testimony whereof I affix my signature. j Y AUGUST HUND.

element adjacent each end thereof, said contact members being alternately arranged around the sides of said piezo-electric element according to the polarity of said piezo-electric crystal element, the contact members 'of one polarity being alternately arranged with respect to the contact members of an opposite polarity, connections between contact members of like polarities adjacent opposite ends of said piezo-electric crystal element, a terminal bus interconnecting the connections of one polarity, and a separate terminal bus interconnecting the connections of the opposite polarity.

8. In a piezoelectric crystal system, a piezo-electric crystal element, a plurality of contact members disposed around the sides of said piezo-electric crystal element adjacent opposite ends thereof, the contact members of negative polarity being alternately positioned with respect to the contact members of positive polarity, connections between contact members of like polarity adjacent each 

